VCSEL Array For HAMR

ABSTRACT

The present disclosure relates to pretreating a magnetic recording head for magnetic media drive. For a heat assisted magnetic recording (HAMR) head, a light source provides the necessary heat for the drive to operation. A vertical cavity surface emitting laser (VCSEL) is mounted to a top surface of a slider. A plurality of laser beams are emitted from the bottom surface of the VCSEL and directed to a corresponding number of waveguide structures within the HAMR head. The waveguide structures feed into a multimode interference (MMI) device that then directs the laser into a single waveguide for focusing on a near field transducer (NFT). The VCSEL lasers are phase coherent and have no mode hopping.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a divisional of co-pending U.S. patent applicationSer. No. 16/908,270, filed Jun. 22, 2020, which is herein incorporatedby reference.

BACKGROUND OF THE DISCLOSURE Field of the Disclosure

Embodiments of the present disclosure generally relate to a magneticrecording head for a magnetic media drive.

Description of the Related Art

The heart of the functioning and capability of a computer is the storingand writing of data to a data storage device, such as a magnetic mediadrive (e.g., hard disk drive (HDD)). The volume of data processed by acomputer is increasing rapidly. There is a need for higher recordingdensity of a magnetic recording medium to increase the function and thecapability of a computer.

In order to achieve higher recording densities, such as recordingdensities exceeding 2 Tbit/in² for a magnetic recording medium, thewidth and pitch of write tracks are narrowed, and thus the correspondingmagnetically recorded bits encoded in each write track is narrowed. Onechallenge in narrowing the width and pitch of write tracks is decreasinga surface area of a main pole of the magnetic recording write head at amedia facing surface of the recording medium. As the main pole becomessmaller, the recording field becomes smaller as well, limiting theeffectiveness of the magnetic recording write head.

Heat-assisted magnetic recording (HAMR) and microwave assisted magneticrecording (MAMR) are two types of energy-assisted recording technologyto improve the recording density of a magnetic recording medium. InHAMR, a laser source is located next to or near the write element inorder to produce heat, such as a laser source exciting a near-fieldtransducer (NFT) to produce heat at a write location of a magneticrecording medium.

HAMR typically utilizes an edge emitting laser diode (EELD) as the lightsource. There are a number of issues with EELD such as the need to mounta sub-mount to a slider which increases cost, mode-hops that cansuddenly change recording power and reduce HAMR HDD capacity, smalldiameter output beams such that there is little alignment tolerance,intense optical mode at the facet which can lower reliability, necessityfor burn-in during manufacturing which increases costs, and a highprofile on the slider which increases disk-to-disk spacing.

Therefore, there is a need in the art for an improved HAMR magneticmedia drive.

SUMMARY OF THE DISCLOSURE

The present disclosure relates to pretreating a magnetic recording headfor magnetic media drive. For a heat assisted magnetic recording (HAMR)head, a light source provides the necessary heat for the drive tooperation. A vertical cavity surface emitting laser (VCSEL) is mountedto a top surface of a slider. A plurality of laser beams are emittedfrom the bottom surface of the VCSEL and directed to a correspondingnumber of waveguide structures within the HAMR head. The waveguidestructures feed into a multimode interference (MMI) device that thendirects the laser into a single waveguide for focusing on a near fieldtransducer (NFT). The VCSEL lasers are phase coherent and have no modehopping.

In one embodiment, a vertical cavity surface emitting laser (VCSEL)device comprises: a chip for mounting on a slider, wherein the chip hasa first surface for facing the slider; and a plurality of laserapertures disposed in the first surface, wherein the plurality of laserapertures are spaced apart by a pitch of between 2 microns and 10microns, wherein the VCSEL device is capable of emitting a plurality oflasers corresponding to the plurality of laser apertures, and whereinthe plurality of lasers operate at the same frequency, and wherein theplurality of laser apertures are linearly arranged.

In another embodiment, a magnetic recording head assembly comprises: aleading shield; a main pole; a near field transducer (NFT) coupledbetween the leading shield and the main pole; a waveguide structurecoupled to the NFT, wherein the waveguide structure comprises: a firstwaveguide coupled to the NFT; a multimodal interference (MMI) devicecoupled to the first waveguide at a first end; and a plurality of secondwaveguides coupled to a second end opposite the first end of the MMIdevice, wherein the plurality of second waveguides extend from the MMIdevice to a top surface of the head assembly, wherein the top surface ofthe head assembly is opposite a media facing surface; and a verticalcavity surface emitting laser (VCSEL) device coupled to the top surface.

In another embodiment, a magnetic media drive comprises: a magneticrecording head, wherein the magnetic recording head comprises: a nearfield transducer (NFT) at a media facing surface (MFS); a waveguidestructure extending between the NFT and a first surface opposite theMFS; and a vertical cavity surface emitting laser (VCSEL) device coupledto the first surface, wherein the VCSEL includes a second surface facingthe first surface, wherein the VCSEL is capable of emitting a pluralityof lasers through the second surface; and a magnetic media facing theMFS.

BRIEF DESCRIPTION OF THE DRAWINGS

So that the manner in which the above recited features of the presentdisclosure can be understood in detail, a more particular description ofthe disclosure, briefly summarized above, may be had by reference toembodiments, some of which are illustrated in the appended drawings. Itis to be noted, however, that the appended drawings illustrate onlytypical embodiments of this disclosure and are therefore not to beconsidered limiting of its scope, for the disclosure may admit to otherequally effective embodiments.

FIG. 1 is a schematic illustration of certain embodiments of a magneticmedia drive including a HAMR magnetic write head.

FIG. 2 is a schematic illustration of certain embodiments of a crosssectional side view of a HAMR write head facing a magnetic disk.

FIGS. 3A and 3B are schematic illustrations of a slider having a VCSELmounted thereto according to one embodiment.

FIGS. 4A-4C are schematic illustrations of a VCSEL according to oneembodiment.

FIG. 5 is a schematic illustration of a waveguide structure of a HAMRhead according to one embodiment.

To facilitate understanding, identical reference numerals have beenused, where possible, to designate identical elements that are common tothe figures. It is contemplated that elements disclosed in oneembodiment may be beneficially utilized on other embodiments withoutspecific recitation.

DETAILED DESCRIPTION

In the following, reference is made to embodiments of the disclosure.However, it should be understood that the disclosure is not limited tospecific described embodiments. Instead, any combination of thefollowing features and elements, whether related to differentembodiments or not, is contemplated to implement and practice thedisclosure. Furthermore, although embodiments of the disclosure mayachieve advantages over other possible solutions and/or over the priorart, whether or not a particular advantage is achieved by a givenembodiment is not limiting of the disclosure. Thus, the followingaspects, features, embodiments and advantages are merely illustrativeand are not considered elements or limitations of the appended claimsexcept where explicitly recited in a claim(s). Likewise, reference to“the disclosure” shall not be construed as a generalization of anyinventive subject matter disclosed herein and shall not be considered tobe an element or limitation of the appended claims except whereexplicitly recited in a claim(s).

The present disclosure relates to pretreating a magnetic recording headfor magnetic media drive. For a heat assisted magnetic recording (HAMR)head, a light source provides the necessary heat for the drive tooperate. A vertical cavity surface emitting laser (VCSEL) is mounted toa top surface of a slider. A plurality of laser beams are emitted fromthe bottom surface of the VCSEL and directed to a corresponding numberof waveguide structures within the HAMR head. The waveguide structuresfeed into a multimode interference (MMI) device that then directs thelaser into a single waveguide for focusing on a near field transducer(NFT). The VCSEL lasers are phase coherent and have no mode hopping.

FIG. 1 is a schematic illustration of certain embodiments of a magneticmedia drive including a HAMR magnetic write head. Such magnetic mediadrive may be a single drive/device or comprise multiple drives/devices.For the ease of illustration, a single disk drive 100 is shown accordingto one embodiment. The disk drive 100 includes at least one rotatablemagnetic recording medium 112 (oftentimes referred to as magnetic disk112) supported on a spindle 114 and rotated by a drive motor 118. Themagnetic recording on each magnetic disk 112 is in the form of anysuitable patterns of data tracks, such as annular patterns of concentricdata tracks (not shown) on the magnetic disk 112.

At least one slider 113 is positioned near the magnetic disk 112. Eachslider 113 supports a head assembly 121 including one or more read headsand one or more write heads such as a HAMR write head. As the magneticdisk 112 rotates, the slider 113 moves radially in and out over the disksurface 122 so that the head assembly 121 may access different tracks ofthe magnetic disk 112 where desired data are written. Each slider 113 isattached to an actuator arm 119 by way of a suspension 115. Thesuspension 115 provides a slight spring force which biases the slider113 toward the disk surface 122. Each actuator arm 119 is attached to anactuator 127. The actuator 127 as shown in FIG. 1 may be a voice coilmotor (VCM). The VCM includes a coil movable within a fixed magneticfield, the direction and speed of the coil movements being controlled bythe motor current signals supplied by control unit 129.

During operation of the disk drive 100, the rotation of the magneticdisk 112 generates an air bearing between the slider 113 and the disksurface 122 which exerts an upward force or lift on the slider 113. Theair bearing thus counter-balances the slight spring force of suspension115 and supports slider 113 off and slightly above the disk surface 122by a small, substantially constant spacing during normal operation.

The various components of the disk drive 100 are controlled in operationby control signals generated by control unit 129, such as access controlsignals and internal clock signals. Typically, the control unit 129comprises logic control circuits, storage means, and a microprocessor.The control unit 129 generates control signals to control various systemoperations such as drive motor control signals on line 123 and headposition and seek control signals on line 128. The control signals online 128 provide the desired current profiles to optimally move andposition slider 113 to the desired data track on magnetic disk 112.Write and read signals are communicated to and from the head assembly121 by way of recording channel 125. Certain embodiments of a magneticmedia drive of

FIG. 1 may further include a plurality of media, or disks, a pluralityof actuators, and/or a plurality number of sliders.

FIG. 2 is a schematic illustration of certain embodiments of a crosssectional side view of a HAMR write head 230 facing a magnetic disk 112.The HAMR write head 230 may correspond to part of the reading/recordinghead assembly 121 described in FIG. 1 or a recording head used in othermagnetic media drives. The HAMR write head 230 includes a media facingsurface (MFS), such as an air bearing surface (ABS) or a gas bearingsurface (GBS), facing the disk 112. As shown in FIG. 2, the magneticdisk 112 and the HAMR write head 230 relatively moves in the directionindicated by the arrows 282 (need to change direction).

The HAMR write head 230 includes a main pole 236 disposed between aleading return pole 234 and a trailing return pole 238. The main pole236 can include a main pole tip 237 at the MFS. The main pole tip 237can include or not include a leading taper and/or a trailing taper. Acoil 260 around the main pole 236 excites the main pole tip 237 toproduce a writing magnetic field for affecting a magnetic medium of therotatable magnetic disk 112. The coil 260 may be a helical structure orone or more sets of pancake structures. The leading shield 234 and/orthe trailing shield 238 can act as the return pole for the main pole236.

The magnetic disk 112 is positioned adjacent to or under the HAMR writehead 230. A magnetic field produced by current in the coil 260 is usedto control the direction of magnetization of bits in the magnetic disk112.

The HAMR write head 230 includes a structure for heating the magneticdisk 112 proximate to where the main pole tip 237 applies the magneticwrite field to the storage media. A waveguide 242 is positioned betweenthe main pole 236 and the leading shield 234. The waveguide 242 canincludes a core layer and a cladding layer surrounding the core layer.The waveguide 242 conducts light from a light source 278 ofelectromagnetic radiation, which may be, for example, ultraviolet,infrared, or visible light. The light source 278 may be, for example, alaser diode, or other suitable laser light source for directing a lightbeam toward the waveguide 242. Various techniques that are known forcoupling the light source 278 into the waveguide 242 may be used. Forexample, the light source 278 may work in combination with an opticalfiber and external optics for directing a light beam to the waveguide242. Alternatively, the light source 278 may be mounted on the waveguide242 and the light beam may be directly coupled into the waveguide 242without the need for external optical configurations. Once the lightbeam is coupled into the waveguide 242, the light propagates through thewaveguide and heats a portion of the media, as the media moves relativeto the HAMR write head 230 as shown by arrows 282.

The HAMR write head 230 can include a near-field transducer (NFT) 284 toconcentrate the heat in the vicinity of the end of the waveguide 242.The NFT 284 is positioned in or adjacent to the waveguide 242 near or atthe MFS. Light from the waveguide 242 is absorbed by the NFT 284 andexcites surface plasmons which travel along the outside of the NFT 284towards the MFS concentrating electric charge at the tip of the NFT 284which in turn capacitively couples to the magnetic disk and heats aprecise area of the magnetic disk 112 by Joule heating. One possible NFT284 for the HAMR write head is a lollipop design with a disk portion anda peg extending between the disk and the MFS. The NFT 284 can be placedin close proximity to the main pole 236. The NFT 284 is relativelythermally isolated and absorbs a significant portion of the laser powerwhile it is in resonance.

FIGS. 3A and 3B are schematic illustrations of a slider 302 having aVCSEL 304 mounted thereto according to one embodiment. The VCSEL 304 ismounted to the slider 302 via a first contact 308 a and a second contact308 b in a first location as shown in FIG. 3B. In one embodiment, theVCSEL 304 is mounted on top of the slider 302, unlike an edge emittinglaser diode (EELD) which typically needs to be first mounted to asub-mount because it is difficult to bond the edge-emitting facet faceof the laser directly to the top of the slider. The VCSEL 304 may have aminimal design structure, such that the dimensions of the VCSEL 304 mayreduce the overall size of the HAMR write head. The VCSEL 304 includes amesa 306 on a bottom surface of the VCSEL 304 facing the slider 302,where the mesa 306 is located between the VCSEL 304 and the slider 302.In FIG. 3B, the VCSEL 304 is shown in phantom to provide bettervisibility to the electrodes 321 on the top surface of the slider 302.The electrodes 321 provide the electrical connection, via anelectrically conductive soldering material, to the electrodes of theVCSEL 304. The electrodes 321, the soldering material, and theelectrodes of the VCSEL 304 collectively form the first contact 308 aand the second contact 308 b. The electrodes 321 extend above the slider302 by a distance of between about 1 micron and about 3 microns.

The VCSEL 304 is capable of emitting a plurality of lasers thatcorrespond to plurality of laser apertures of the mesa 306, where eachof the plurality of lasers is aligned with the plurality of laserapertures (shown in FIG. 4C) of the mesa 306. Furthermore, the slider302 includes a plurality of spot size converters 314 a-314 n that matchthe position and number of input lasers emitted by the VCSEL 304. Thespot size converters 314 a-314 n extend from the top surface of theslider 302 facing the VCSEL 304. The mesa 306 is spaced from the topsurface of the slider 302 by a first distance 318 of about 1 μm to about20 μm. The mesa 306 includes a plurality of laser apertures, such asabout 2 laser apertures to about 16 apertures. The previously listedvalues are not intended to be limiting, but to provide an example of anembodiment. The mesa is part of the VCSEL 304 chip and the apertures areon the surface of the mesa 306. The mesa 306 is an optional reliefstructure on the surface of the VCSEL 304.

The number of lasers mentioned above that the VCSEL 304 is capable ofemitting matches the number of laser apertures of the mesa 306 as wellas the number of spot size converters 314 a-314 n. Each laser, and henceeach spot size converter 314 a-314 n is spaced apart by a seconddistance. The second distance between each of the spot size converters314 a-314 n is about 2 μm to about 10 μm. Furthermore, each of theplurality of lasers emitted by the VCSEL 304 operates at the samefrequency and are phase coherent. For example, adjacent apertures may bein-phase or out-of-phase with each other. Each laser of the plurality oflasers emitted by the VCSEL 304 has a power level of between about 1 mWto about 10 mW. The previously listed value is not intended to belimiting, but to provide an example of an embodiment. The plurality oflasers each has an active region (e.g., an area where the laser excitedelectrons). These active regions are spaced close enough to enablecoupling and phase coherence to occur.

The slider 302 includes a plurality of bonding pad studs 312 a-312 n,such as about 2 bonding pad studs to about 32 bonding pad studs. Thebonding pad studs 312 a-312 n have a first width 320 of about 25 μm,where the spacing between adjacent bonding pad studs 312 a-312 n isabout 32 μm. The previously listed values are not intended to belimiting, but to provide an example of an embodiment. The plurality ofspot size converters 314 a-314 n are disposed at a location disposedbetween adjacent bonding pad studs 312 a-312 n. In the embodiment shownin FIG. 3A, the spot size converters 314 a-314 n are disposed betweenbonding pad studs 312 c and 312 d. Thus, in one example embodiment, allof the spot size converters 314 a-314 n need to fit within a lineardistance of about 32 μm. Furthermore, the plurality of lasers, andhence, the plurality of spot size converters 314 a-314 n are linearlyarranged. Each spot size converter 314 a-314 n is spaced about 2 μm toabout 10 μm from the adjacent spot size converter 314 a-314 n.

The plurality of spot size converters 314 a-314 n feed into a multimodeinterference (MMI) device 310 that is disposed within the slider 302.The MMI device 310 combines the laser light fed from the output of theplurality of spot size converters 314 a-314 n at a first end, and emitsa single laser through a single output waveguide 316. The singlewaveguide 316 emits laser light from the MMI device 310 that includesthe combined power of the plurality of input lasers from the pluralityof spot size converters 314 a-314 n accepted by the MMI device 310. Thesingle output mode is needed to properly concentrate the optical powerand couple to the NFT. Proper operation of the MMI typically requiresstable phase coherence between the inputs.

FIG. 4A is a schematic illustration of the side view of the VCSEL 400,FIG. 4B is a schematic illustration of the top view of the VCSEL 400,and FIG. 4C is a schematic illustration of the bottom view of the VCSEL400 according to various embodiments. The side surface 402 of the VCSEL400 includes a height of about 75 μm to about 150 μm and a length ofabout 100 μm to about 250 μm. The top surface 404 and the bottom surface406 of the VCSEL 400 include the same dimensions. The dimensions of thetop surface 404 and the bottom surface 406 include a width of about 150μm and a length of about 150 μm, where the length of the top surface404, the bottom surface 406, and the side surface 402 are equal. TheVCSEL 400 may have a plurality of electrodes 411 on the top surface 404as shown in FIG. 4B, and they may be used to energize the VCSEL duringactive alignment before bonding.

In FIG. 4C, a plurality of laser apertures 408 a-408 n are disposed onthe bottom surface 406 of the VCSEL 400. The number of laser apertures408 a-408 n matches the number of spot size converters of the slider,such as the spot size converters 314 a-314 n of FIG. 3A. Each laseraperture 408 a-408 n is spaced by a distance 412 of about 2 μm to about10 μm from the adjacent laser aperture 408 a-408 n. Furthermore, thelaser apertures 408 a-408 n are aligned about a center line and each ofthe plurality laser apertures 408 a-408 n are aligned to a correspondinginput laser. In addition to being aligned to each input laser, the laserapertures 408 a-408 n are aligned with a corresponding laser aperture ofthe mesa, such as the laser apertures of the mesa 306 of FIG. 3.

As shown in FIG. 4C, the bottom surface 406 of the VCSEL 400 has aplurality of electrodes 410 thereon to that function as anode andcathode, and mate with electrodes 321 of the slider 302 via solderingmaterial. The electrodes 410 extend from the bottom surface 406 of theVCSEL 400 towards the slider for a distance of between about 1 micro andabout 3 microns. Thus, in one embodiment, the gap between the VCSEL 400and the slider 302 is between about 2 microns and about 6 microns.Additionally, the VCSEL 400 has a length 428 of between about 100microns and about 200 microns. The VCSEL 400 also have a length 426 ofbetween about 100 microns and about 200 microns. The apertures 408 a-408n each have a diameter of between about 1.5 microns and about 8 micronsand are on a 2 micron to 10 micron pitch. The center of the apertures408 a-408 n are spaced from the side surface 402 by a distance 422 ofbetween about 35 microns and about 50 microns. The center of theapertures 408 a-408 n are spaced from the electrodes 410 by a distance424 of between about 75 microns and about 90 microns.

FIG. 5 is a schematic illustration of a waveguide structure 500 of aHAMR head according to one embodiment. The slider, such as the slider302 of FIG. 3, includes the waveguide structure 500 that includes afirst spot size converter 506 that extends from the NFT to the MMIdevice 502. The waveguide structure 500 also includes a plurality ofsecond spot size converters 504 a-504 n, such as about 2 second spotsize converters to about 8 second spot size converters. The number ofsecond spot size converters 504 a-504 n matches the number of laserapertures 408 a-408 n of the VCSEL 400 described in FIG. 4C, the numberof laser apertures of the mesa 306 described in FIG. 3A, and the numberof spot size converters 314 a-314 n described in FIG. 3A.

The plurality of second spot size converters 504 a-504 n fit within thespacing between the bonding pad studs, such as the bonding pad studs 312a-312 n, such that the distance between the leftmost second spot sizeconverter 504 a and the rightmost second spot size converter 504 n isless than the space of about 32 μm between the bonding pad studs.Furthermore, the plurality of laser apertures 408 a-408 n of the VCSELdescribed in FIG. 4C, the plurality of laser apertures of the mesa 306described in FIG. 3A, and the plurality of emitted lasers, are eachaligned with a corresponding second spot size converters 504 a-504 n.

As noted above, the waveguide structure 500 further includes a MMIdevice 502. The MMI device 502 may be the same as the MMI device 310 ofFIG. 3. The first spot size converter 506 at a first end is coupled tothe MMI device 502 at a first end and the plurality of second spot sizeconverters 504 a-504 n at a second end are coupled to the MMI device 502at a second end that is opposite of the first end of the MMI device 502.The first spot size converter 506, at a second end, is further coupledto a NFT, such as the NFT 284 of FIG. 2.

Furthermore, the core width of the second spot size converters 504 a-504n gradually increases from about 150 nm to about 600 nm, along thedirection towards the MMI device 502. At 150 nm, the spot size ismatched to the large VCSEL mode size of a few microns. At 600 nm, thewaveguide mode is only a few hundred nanometers before going into theMMI device 502.

VCSELs have a number of significant advantages for use as the lightsource in HAMR. The edge emitting laser diode (EELD) used today istypically mounted to a sub-mount because it is difficult to bond theedge-emitting facet face of the laser directly to the top of the slider.This sub-mount is then bonded to the slider. A VCSEL can easily havebonding electrodes on the surface-emitting face which match tocorresponding electrodes on the top surface of the slider. Theseelectrodes can be bonded together by laser-assisted solder reflow andcan also serve as electrical connections for energizing the laser. Byeliminating the need for a sub-mount, the light source cost can besignificantly reduced. The VCSEL laser facet is made in a wafer levelprocess which further lowers cost relative to EELDs. A VCSEL output beamis also larger and more circular than that of an EELD which increasesthe alignment tolerance and coupling efficiency to the slider spot sizeconvertor. VCSELs are known to have higher reliability than EELDs due tolarger, less intense optical mode and the wafer facet process. As aresult, VCSELs do not require burn-in during manufacturing which furtherlowers cost. Since the VCSEL cavity length is shorter than EELDs, andbecause the laser is mounted on top of the slider, the lower overallheight allows for a reduced disk-to-disk spacing, potentially moredisks, and for higher HDD capacity.

Further, VCSELs have mode hop-free operation due to very short cavitylength with one longitudinal mode and DBR mirror selectivity while EELDssuffer from mode hops. Mode hopping can cause a small (typically 1-2%)change in laser power to suddenly occur during the recording process.The possibility of a track width change and bit shift must be accountedfor, which reduces the capacity of the HDD.

The primary technical issue with VCSELs is the relatively low outputpower relative to EELDs. Multimode VCSELs can have larger output powerthan single mode VCSELs but single mode operation is required by thewaveguides and NFTs that are used to create the heat spot in the diskfor HAMR. Single mode VCSELs typically have only about 2 mW of maximumoutput power, far short of the 10-20 mW needed for HAMR. The outputcannot be efficiently increased by combining the outputs from multipleseparate VCSELs because of decoherence between the wave fronts. If theactive region of adjacent VCSELs are brought very close together, thewave functions will overlap enough to create coupling and phasecoherence between their outputs. With the right VCSEL design and lightdelivery scheme, these outputs may be combined into a single waveguidewith the necessary 5-10 mW of single mode power needed by the NFT forHAMR.

In one embodiment, a vertical cavity surface emitting laser (VCSEL)device comprises: a chip for mounting on a slider, wherein the chip hasa first surface for facing the slider; and a plurality of laserapertures disposed in the first surface, wherein the plurality of laserapertures are spaced apart by a distance of between about 2 microns andabout 10 microns, wherein the VCSEL device is capable of emitting aplurality of lasers corresponding to the plurality of laser apertures,wherein the plurality of lasers operate at the same frequency, andwherein the plurality of laser apertures are linearly arranged. TheVCSEL device is capable of emitting a plurality of lasers that are phasecoherent. The plurality of laser apertures includes 2-8 laser apertures.The VCSEL device is capable of emitting a plurality of laserscorresponding to the plurality of laser apertures, and wherein eachlaser of the plurality of lasers has a power level of between about 1 mWand about 10 mW. The first surface comprises a mesa and wherein theplurality of laser apertures are disposed in the mesa, wherein theplurality of laser apertures are spaced apart by a distance of betweenabout 2 microns and about 10 microns. The VCSEL device further comprisesa plurality of electrodes coupled to the first surface. The electrodesextend about 10 microns, and more preferably up to 2 microns from thefirst surface towards the slider. A magnetic media drive comprising theVCSEL device is also disclosed.

In another embodiment, a magnetic recording head assembly comprises: aleading shield; a main pole; a near field transducer (NFT) coupledbetween the leading shield and the main pole; a waveguide structurecoupled to the NFT, wherein the waveguide structure comprises: a firstwaveguide coupled to the NFT; a multimodal interference (MMI) devicecoupled to the first waveguide at a first end; and a plurality of secondwaveguides coupled to a second end opposite the first end of the MMIdevice, wherein the plurality of second waveguides extend from the MMIdevice to a top surface of the head assembly, wherein the top surface ofthe head assembly is opposite a media facing surface; and a verticalcavity surface emitting laser (VCSEL) device coupled to the top surface.The VCSEL has a plurality of laser apertures that align with theplurality of second waveguides. The plurality of laser apertures arealigned with the plurality of second waveguides in a near field. Theplurality of laser apertures are spaced from the top surface by a firstdistance of between about 1 microns to about 20 microns. The pluralityof second waveguides comprises 2-16 second waveguides. A magnetic mediadrive comprising the magnetic recording head assembly is also disclosed.

In another embodiment, a magnetic media drive comprises: a magneticrecording head, wherein the magnetic recording head comprises: a nearfield transducer (NFT) at a media facing surface (MFS); a waveguidestructure extending between the NFT and a first surface opposite theMFS; and a vertical cavity surface emitting laser (VCSEL) device coupledto the first surface, wherein the VCSEL includes a second surface facingthe first surface, wherein the VCSEL is capable of emitting a pluralityof lasers through the second surface; and a magnetic media facing theMFS. The second surface is spaced between about 1 microns and about 20microns from the first surface. The waveguide structure has a width thatis less than a width between adjacent electrodes of a slider upon whichthe magnetic recording head is disposed. The VCSEL is capable ofemitting a plurality of lasers that are phase coherent. The waveguidestructure comprises a multimodal interference (MMI) device that isdisposed between the NFT and the first surface. The VCSEL is capable ofemitting a plurality of lasers and wherein the plurality of lasers haveactive regions that at least partially overlap.

While the foregoing is directed to embodiments of the presentdisclosure, other and further embodiments of the disclosure may bedevised without departing from the basic scope thereof, and the scopethereof is determined by the claims that follow.

What is claimed is:
 1. A vertical cavity surface emitting laser (VCSEL) device, comprising: a chip for mounting on a slider, wherein the chip has a first surface for facing the slider; and a plurality of laser apertures disposed in the first surface, wherein the plurality of laser apertures are spaced apart by a distance of between about 1 microns and about 20 microns, wherein the VCSEL device is capable of emitting a plurality of lasers corresponding to the plurality of laser apertures, wherein the plurality of lasers operate at the same frequency, and wherein the plurality of laser apertures are linearly arranged.
 2. The VCSEL device of claim 1, wherein the VCSEL device is capable of emitting a plurality of lasers that are phase coherent.
 3. The VCSEL device of claim 1, wherein the plurality of laser apertures includes 2-16 laser apertures.
 4. The VCSEL device of claim 1, wherein each laser of the plurality of lasers has a power level of between about 1 mW and about 10 mW.
 5. The VCSEL device of claim 1, wherein the first surface comprises a mesa and wherein the plurality of laser apertures are disposed in the mesa, and wherein the plurality of laser apertures are spaced apart by a distance of between about 2 microns and about 10 microns.
 6. The VCSEL device of claim 1, further comprising a plurality of electrodes coupled to the first surface.
 7. The VCSEL device of claim 6, wherein the electrodes extend up to 2 microns from the first surface towards the slider.
 8. A magnetic media drive comprising the VCSEL device of claim
 1. 9. A vertical cavity surface emitting laser (VCSEL) device, comprising: a chip for mounting on a slider, wherein the chip has a first surface for facing the slider, wherein the first surface has a mesa, wherein the mesa has a plurality of apertures, wherein the plurality of apertures are spaced apart by a distance of between about 1 microns and about 20 microns; a first electrode disposed on the first surface, wherein the first electrode is coupled to the first surface; and a second electrode disposed on the first surface, wherein the second electrode is coupled to the first surface, wherein the VCSEL device is capable of emitting a plurality of lasers corresponding to the plurality of apertures, wherein the plurality of lasers operate at the same frequency, and wherein the plurality of apertures are linearly arranged.
 10. The VCSEL device of claim 9, wherein the first electrode is coupled to the first surface via a soldering material.
 11. The VCSEL device of claim 10, wherein the soldering material is electrically conductive.
 12. The VCSEL device of claim 11, wherein the second electrode is coupled to the first surface via a soldering material.
 13. The VCSEL device of claim 12, wherein the soldering material is electrically conductive.
 14. The VCSEL device of claim 9, wherein each laser of the plurality of lasers have a power level of between about 1 mW and about 10 mW.
 15. The VCSEL device of claim 9, wherein the apertures are spaced apart by a distance of between about 2 microns and about 10 microns.
 16. The VCSEL device of claim 9, wherein the VCSEL device is capable of emitting a plurality of lasers that are phase coherent.
 17. The VCSEL device of claim 9, wherein the plurality of laser apertures includes 2-16 laser apertures.
 18. The VCSEL device of claim 9, wherein the first electrode and the second electrode extend up to 2 microns from the first surface.
 19. The VCSEL device of claim 9, wherein the chip has a height of between about 75 μm and about 150 μm and a length of between about 100 μm and about 250 μm.
 20. A magnetic media drive comprising the VCSEL device of claim
 9. 